Lighthouses have been guiding ships since ancient times, with the earliest known lighthouse, the Pharos of Alexandria, built around 280 BC in Egypt. These structures were designed to mark dangerous coastlines, safe entry points to harbors, and to assist in aerial navigation. Over the centuries, lighthouses evolved in design and technology, incorporating features like rotating lights and foghorns. By the 19th century, lighthouses became more widespread, particularly in Europe and North America. The introduction of electricity in the early 20th century revolutionized lighthouse operation, allowing for brighter and more reliable signals. Today, many lighthouses are automated, but they remain iconic symbols of maritime history.